SQL Server 2017

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create table TestSAMP (
id int identity(1,1),
target1 nvarchar(max),
target2 nvarchar(max),
target3 nvarchar(max),
target4 nvarchar(max),
doprcoess  int default(1)
)

--VALID SET DOPROCESS FALG TO 1
INSERT INTO TestSAMP(target1,target2,target3,target4) VALUES('T1','T2','T3','T4')
--NOTVALID SET DOPROCESS FALG TO 0 DUE TO THE DATA IS MISSING IN SEQUENCE 
INSERT INTO TestSAMP(target1,target2,target3,target4) VALUES('T1','','T3','T4')
--VALID SET DOPROCESS FALG TO 1 As if data is present it should be present insequence in below t1 t2 as they arfe in sequence
INSERT INTO TestSAMP(target1,target2,target3,target4) VALUES('T1','T2','','')
--NOTVALID SET DOPROCESS FALG TO 0 DUE TO THE DATA IS MISSING IN SEQUENCE where T4 data is provided and not in T3
INSERT INTO TestSAMP(target1,target2,target3,target4) VALUES('T1','T2','','T4')
INSERT INTO TestSAMP(target1,target2,target3,target4) VALUES('','','','T4')
INSERT INTO TestSAMP(target1,target2,target3,target4) VALUES('','','','')
6 rows affected

SELECT *, CASE WHEN squashed LIKE '%IGI%' THEN 0 ELSE 1 END AS new_doprocess
FROM TestSAMP t
CROSS APPLY(SELECT STRING_AGG(CASE WHEN t = '' THEN 'G' ELSE 'I'END, '') r
             FROM (
                 VALUES (1,id, target1),
                        (2,id, target2),
                        (3,id, target3),
                        (4,id, target4)) sub(rn, id, t)) s
CROSS APPLY (SELECT replace(replace(replace(replace(replace(replace(s.r,'G','<>'),'><',''),'<>','G')
         ,'I','<>'),'><',''),'<>','I')) AS sub(squashed)
ORDER BY t.id


id
target1
target2
target3
target4
doprcoess
r
squashed
new_doprocess


1
T1
T2
T3
T4
1
IIII
I
1

2
T1

T3
T4
1
IGII
IGI
0

3
T1
T2


1
IIGG
IG
1

4
T1
T2

T4
1
IIGI
IGI
0

5



T4
1
GGGI
GI
1

6




1
GGGG
G
1

id	target1	target2	target3	target4	doprcoess	r	squashed	new_doprocess
1	T1	T2	T3	T4	1	IIII	I	1
2	T1		T3	T4	1	IGII	IGI	0
3	T1	T2			1	IIGG	IG	1
4	T1	T2		T4	1	IIGI	IGI	0
5				T4	1	GGGI	GI	1
6					1	GGGG	G	1